[Mesa-dev] [RFCv2 03/13] nir: allow pre-resolved sampler uniform locations

[Ilia Mirkin]

On Thu, Nov 19, 2015 at 2:54 PM, Rob Clark <robdclark at gmail.com> wrote:
> On Mon, Nov 9, 2015 at 4:08 PM, Timothy Arceri <t_arceri at yahoo.com.au> wrote:
>> On Mon, 2015-11-09 at 07:43 -0500, Rob Clark wrote:
>>> On Sun, Nov 8, 2015 at 7:58 PM, Timothy Arceri <t_arceri at yahoo.com.au>
>>> wrote:
>>> > On Sun, 2015-11-08 at 15:12 -0500, Rob Clark wrote:
>>> > > From: Rob Clark <robclark at freedesktop.org>
>>> > >
>>> > > With TGSI, the ir_variable::data.location gets fixed up to be a stage
>>> > > local location (rather than program global).  In this case we need to
>>> > > skip the UniformStorage[location] lookup.
>>> > > ---
>>> > >  src/glsl/nir/nir_lower_samplers.c | 23 ++++++++++++++++-------
>>> > >  1 file changed, 16 insertions(+), 7 deletions(-)
>>> > >
>>> > > diff --git a/src/glsl/nir/nir_lower_samplers.c
>>> > > b/src/glsl/nir/nir_lower_samplers.c
>>> > > index 5df79a6..d99ba4c 100644
>>> > > --- a/src/glsl/nir/nir_lower_samplers.c
>>> > > +++ b/src/glsl/nir/nir_lower_samplers.c
>>> > > @@ -130,14 +130,18 @@ lower_sampler(nir_tex_instr *instr, const struct
>>> > > gl_shader_program *shader_progr
>>> > >        instr->sampler_array_size = array_elements;
>>> > >     }
>>> > >
>>> > > -   if (location > shader_program->NumUniformStorage - 1 ||
>>> > > -       !shader_program->UniformStorage[location].opaque[stage].active)
>>> > > {
>>> > > -      assert(!"cannot return a sampler");
>>> > > -      return;
>>> > > -   }
>>> > > +   if (!shader_program) {
>>> > > +      instr->sampler_index = location;
>>> > > +   } else {
>>> > > +      if (location > shader_program->NumUniformStorage - 1 ||
>>> > > +          !shader_program
>>> > > ->UniformStorage[location].opaque[stage].active) {
>>> > > +         assert(!"cannot return a sampler");
>>> > > +         return;
>>> > > +      }
>>> > >
>>> > > -   instr->sampler_index +=
>>> > > -      shader_program->UniformStorage[location].opaque[stage].index;
>>> > > +      instr->sampler_index =
>>> > > +         shader_program->UniformStorage[location].opaque[stage].index;
>>> >
>>> > Hi Rob,
>>> >
>>> > This will break arrays as instr->sampler_index is increamented inside
>>> >  calc_sampler_offsets()
>>>
>>> oh, whoops, I didn't notice that.. ok, that part is easy enough to fix..
>>>
>>> > calc_sampler_offsets() also modifies the value of location is this what
>>> > you
>>> > want? I would assume not as we are counting uniforms not just samplers
>>> > here.
>>>
>>> hmm, tbh I'm not entirely sure..  offhand, what piglit's should I
>>> check?
>>
>> tests/spec/arb_gpu_shader5/execution/sampler_array_indexing
>>
>> Contains the tests you probably want to try out.
>
> oh, hmm, looks like they all need at least gl3.2..

Not to mention ARB_gpu_shader5 :)

  -ilia